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Where did the moon come from? Was there life on Mars before? Vox Media, Inc.）The tech podcast “Unexplainable” invites experts to talk about the seven unsolved mysteries of the solar system.
Today, people think that technology is very developed, but it turns out that scientists do not have answers to many seemingly simple questions. Scientist Rebecca Boyle, who was invited to the show, said: “I know a lot of people take it for granted that the moon is there, while galaxies, nebulae, stars, exoplanets are more mysterious. of.”
Indeed, now scientists have detected all kinds of magical celestial objects in the distant deep space, and they are also curious about how the first galaxy in this universe was formed, and what the inside of a black hole that absorbs all matter looks like. There are various questions. But here we are—there are many mysteries in the interior of the solar system that are no less magical than deep space.
Exploring the answers to various puzzles within our solar system can help expand our knowledge of other galaxies. The experts at Unexplainable talk about these seven unsolved mysteries in the solar system.
1. What event destroyed Venus?
The surface of Venus today is similar to the “hell” described in literary and artistic works. The temperature is as high as 482°C, making it the second warmest planet in the solar system. Venus’ atmosphere is almost entirely made up of carbon dioxide gas, causing a strong greenhouse effect. The landforms are made of volcanic rocks, and the mountains are filled with highly corrosive sulfuric acid fumes. The pressure on the surface of Venus is about 92 times the pressure at sea level on Earth.
The volcanic surface of Venus. (NASA/JPL)Some scientists estimate that Venus’ previous environment was similar to Earth’s, with liquid water and oceans on its surface. Robin George Andrews, author of Super Volcanoes: What They Reveal about Earth and the Worlds Beyond, said: “Venus and Earth are like They are sibling planets. They were made at the same time and from the same materials, and Venus is like hell and Earth like heaven. Why is one planet hell and another neighboring planet like heaven?”
At present, scientists have put forward two speculations. One is that the sun has roasted Venus, and the other is that volcanic activity destroyed Venus.
2. Where did the moon come from?
Before humans landed on the moon, scientists thought that the moon, like various planets, was formed by the gathering of dust and matter left over after the formation of the sun. However, in the last century, the Apollo program of the United States sent astronauts to the moon, and analysis of the samples collected showed that the moon should not have formed in this way.
Meradith Hoddinott, senior producer of Unexplainable, said on the show that the moon’s surface is covered with a special kind of stone, Anorthite, “which is shimmering and light in color. It is these stones that make the moon shine in the night sky. At that time, scientists thought that only a very special process would produce this kind of stone.”
Scientists believe the stones were created in a large-scale high-temperature event, “that would have had such a huge amount of energy that it melted the entire surface of the moon (to produce a lot of these stones).” Hodinot said that so far, scientists have It’s impossible to guess what kind of event could have created the moon and created such an effect.
The moon’s surface is covered with a special kind of stone, anorthite, that provides some level of illumination in the night sky. (NASA)Note:According to Wikipedia, anorthite is one of the plagioclase minerals, and more than 90% of the plagioclase that makes up the lunar surface is plagioclase. Due to the low content of sodium on the moon, most of the plagioclase contained is anorthite.
3. Are human fecal bacteria still alive on the moon?
In addition to leaving human footprints on the moon, the Apollo program also left a special gift – excrement.
Going to the toilet in space is not as convenient as it is on Earth, because there is no gravity, so the excrement will float in the air. Later, after a series of humanized improvements, the fecal collection system is now relatively scientific. Excrement is automatically stored in a well-sealed bag for easy return to Earth.
The astronauts landing on the moon in 1969 left behind garbage bags containing excrement. (NASA)Bringing back various samples by astronauts is an important step in the human lunar landing plan. At that time, in order to bring back more lunar samples, astronauts chose to directly discard useless human excrement on the moon. With the increase in the number of landings in the United States, it has accumulated as many as 96 bags. The National Aeronautics and Space Administration (NASA) announced in 2017 that it would bring feces from the moon back to Earth.
Such a test was not thought of at the time, it was just a decision made to lighten the load on the astronauts’ return journey. Now, however, this behavior has become an accidental experiment: Can microorganisms on Earth survive and thrive in an environment as extreme as the moon?
If they can survive on the moon, that means there is a chance that these microbes could spread from planet to planet through meteorites or other space debris.
4. Have other civilizations existed before humans on Earth?
Scientists have always been curious to explore whether other intelligent life and civilization exist in space. Climatologist Gavin Schmidt and astrophysicist Adam Frank talk about the possibility that other types of intelligent life existed on Earth before, say hundreds of millions of years ago, and are now buried deep underground.
There may have been other intelligent life and prehistoric civilizations in the blue home of mankind. (NASA)Schmidt and Frank believe that exploring this question can help understand the probability of life on any planet leaving traces of their existence over a period of hundreds of millions of years. After the human civilization, can life hundreds of millions of years later find clues that we once existed?
5. Can humans redirect asteroids?
An asteroid hitting the Earth is an inevitable catastrophe, it’s just a matter of when and how big it will be. Scientists are conducting a daring experiment in launching a spacecraft to smash into an asteroid, trying to use the force of the impact to change its orbit.
Schematic diagram of NASA launching a spacecraft to hit an asteroid. (NASA)This is NASA’s “Double Asteroid Redirection Test (DART)” mission. NASA launched SpaceX’s “Falcon 9” (Falcon 9) rocket from the Vandenberg Space Base in California on the evening of November 23, 2021. It is expected to be from September 26 to October 1 this year. Today, it can hit the asteroid Dimorphos at a speed of about 6.7 kilometers per second, hoping to successfully change its orbit.
Schematic diagram of NASA launching a spacecraft to hit an asteroid. (Handout/European Space Agency/AFP)Could the impact change the asteroid’s orbit? Scientists wait and see.
6. Was there life on Mars before?
Mars today is a barren planet. But multiple pieces of evidence show that there was liquid water on Mars 4 billion years ago, and it also had an environment similar to Earth’s now. NASA astrobiologist Lindsay Hays said: “Now seeing traces of huge river deltas on Mars, this means that Mars has not only had extraterrestrial liquid water, but also has a long historical period. With the scouring of flowing liquid water, the sediments built up and formed the landscape we see today.”
Huge river delta area in Jezero impact crater on Mars. (NASA/JPL-Caltech/ASU)Since there is water, there is likely to be life. Last year, NASA sent a new rover (Perseverance) to Mars in an effort to find an answer to the question “Is there life on Mars?” If evidence is found that there was indeed life on Mars, it will be an epoch-making cognition that will change the way humans view life in the universe.
Anorthite crystals mixed in basalt found at Mount Vesuvius. (Wikipedia)Note:Extraterrestrial liquid water means liquid water outside the Earth. Extraterrestrial liquid water is a subject of widespread concern as it is considered a key prerequisite for the existence of extraterrestrial life.
7. Where is the ninth planet of the solar system?
In the solar system, there used to be a total of nine planets. In addition to these larger planets, there are many smaller planets in the solar system, which are distributed in the asteroid belt between Mars and Jupiter. Pluto was originally the ninth largest planet in the solar system, but in 2006, the International Astronomical Union (IAU) redefined the planet, and Pluto was excluded and classified as a “dwarf planet”. Now, there are only eight planets left in the solar system.
Pluto as seen by the New Horizons probe in 2015. (NASA/JHUAPL/SwRI)But “there’s a lot of clues that beyond Neptune, there’s a huge hidden planet waiting to be discovered. It’s the real ninth planet,” astronomer Mike Brown said on the show. ”
Brown is referring to the fact that scientists have found that many celestial bodies in the outer solar system seem to be affected by the gravity of a certain celestial body, which leads scientists to speculate that there is also a huge planet hidden there.
But it’s hard. “It’s like looking for a grain of black sand on the beach,” Brown said. “It’s so hard to find this ‘Planet Nine’.”